Prosthetic foot

Abstract

Embodiments of low cost prosthetic feet include a footplate with a connection mechanism embedded within a first foam element having a first stiffness. A second foam element is bonded to the footplate and has a recess in a proximal surface and a stiffness greater than the first foam element. The second foam element may have a portion extending past the terminal end of the footplate. A cosmesis encloses the components of the prosthetic foot. A third foam element that extends through the cosmesis into the second foam element may be provided. The third foam element may have a higher stiffness than the first and second foam elements.

1. A prosthetic foot comprising:
 a first foam element having a first stiffness; 
 a second foam element having a second stiffness different than the first stiffness of the first foam element; 
 a resilient footplate embedded within the first and second foam elements, and having proximal and distal surfaces, and anterior and posterior portions; 
 wherein the first foam element is disposed along the proximal surface of the footplate and the second foam element is disposed along substantially the entire distal surface of the footplate; 
 a third foam element having a third stiffness that is greater than the first and second stiffnesses of the first and second foam elements, respectively, the third foam element extending into the second foam element spaced from the distal surface of the footplate; and 
 an outer shell defining a cosmesis surrounding the first and second foam elements wherein the third foam element extends through a distal posterior surface of the cosmesis into a distal posterior portion of the second foam element. 
 
     
     
       2. The prosthetic foot according to  claim 1 , wherein the third foam element has proximal and distal surfaces, and is in the shape of a trapezoid with the distal surface larger than the proximal surface. 
     
     
       3. The prosthetic foot according to  claim 1 , wherein the second stiffness of the second foam element is greater than the first stiffness of the first foam element. 
     
     
       4. The prosthetic foot according to  claim 1 , wherein the second stiffness of the second foam element is less than the first stiffness of the first foam element. 
     
     
       5. The prosthetic foot according to  claim 1 , wherein the stiffness of the cosmesis is within the range of 45-55 on the Shore A scale. 
     
     
       6. The prosthetic foot according to  claim 1 , wherein the stiffness of the first foam element is within the range of 45-55 on the Shore A scale. 
     
     
       7. The prosthetic foot according to  claim 1 , wherein the stiffness of the second foam element is about 60 on the Shore A scale. 
     
     
       8. The prosthetic foot according to  claim 1 , wherein the footplate is a carbon or carbon fiber composite footplate. 
     
     
       9. The prosthetic foot according to  claim 1 , wherein the footplate is a plastic or fiber reinforced plastic footplate. 
     
     
       10. The prosthetic foot according to  claim 1 , wherein the footplate is a molded chopped fiber footplate.